sales@ipcb.com
Milling PCB board is a controlled-depth milling process that removes specific areas of circuit board material when necessary. It is primarily used for milling recesses. These recesses can range from simple grooves cut into the board for component mounting to fully plated conductive structures connecting multiple layers. It is also used to cut heat sink cavities. While simple operations are performed mechanically, removing the underlying copper foil is accomplished using a laser. Unlike chemical etching, PCB milling is typically a non-chemical process, allowing it to be performed in a typical office or laboratory setting without exposure to hazardous chemicals. High-quality circuit boards can be produced using either process.
With milling PCB board, board quality primarily depends on the system's true or weighted milling accuracy and control, as well as the condition of the milling cutter (sharpness, temper), and its respective feed/rotation speed. In contrast, with chemical etching, board quality depends on the accuracy and/or quality of the mask used to protect the copper from chemical attack, as well as the state of the etching chemistry.
milling pcb board
Milling PCB board can be performed using three different machines depending on the needs:
1. Laser Milling Process
Laser technology uses a high-powered laser beam to cut custom designs and shapes from circuit board material. It can perform cutting, engraving, and marking. The process involves beam generation, beam focusing, heating and melting, material ejection, and beam movement. This process is more precise and uses less power than other methods, and it doesn't use a drill, which prevents damage to the board. Because laser milling offers this non-contact surface removal option, it is an excellent choice for RF and microwave boards requiring precise geometric accuracy.
2. CNC Routers
CNC routers are computer-controlled machines that mount a milling head or spindle. Depending on the needs, CNC routers can be either mobile gantry or fixed bridge, with the table moving beneath the milling spindle. Alternatively, they can be handheld, with the operator moving the machine to the desired cutting position and then fine-tuning it using the CNC router's controls. CAM software creates a model of the board on a computer and then creates tool paths that the machine tool follows milling PCB board.
3. Carbide End Mills
End mills made of solid carbide are called carbide end mills. These tools are used for engraving and creating signage, machining graphite electrodes, circuit board prototypes, electronic components, and fiberglass. They are primarily a type of milling cutter made of carbide. Milling has a variety of applications, including contour milling, face milling, profile milling, and plunge milling. End mills are designed for axial cutting.
Advantages of Milling PCB Board
Milling PCB Board is advantageous for prototyping and some specialized PCB designs. One of the biggest advantages of CNC milling machines is that they can handle milling, drilling, and cutting operations simultaneously, helping to speed up the prototype production process. They can perform drilling, milling, and cutting simultaneously. Furthermore, because they do not involve hazardous chemicals, they are ideal for mass production.
In some cases, PCBs produced by milling are difficult to achieve with wet etching and require subsequent manual drilling, both of which incur higher costs compared to traditional milling PCB board.
Milling PCB Board Design Parameters
The minimum milling cutter diameter is 0.8mm, the standard milling cutter diameter is 2.0mm, and the special milling cutter diameter is 0.8mm ≤ Ø ≤ 2.0mm. The internal and external contours of the board can be machined according to customer specifications. The external corners of the contours can be 90° or rounded according to customer requirements. However, the minimum radius of the internal corners must be equal to the milling cutter radius. To prevent measurement and sizing issues during the milling PCB board process, a 0.2mm line width should be used to indicate the internal and external contours. Generally, traces should be centered on the circuit. Care should be taken not to mill copper to ensure board durability and reduce the risk of injury.
Specific Applications of Milling PCB Board
1. Paneling: In mass production, multiple PCBs are bonded together for manufacturing and then cut into individual boards from the panel. This application is particularly suitable for mass manufacturing and assembly of consumer electronics.
2. Complex Shape Shaping: By cutting along the designed path, the final shape of the PCB board can be shaped, including complex external contours, which is important when creating complex designs. Creating Grooves and Grooves: Milling grooves or grooves of a specific depth and width into a PCB.
3. Creating Details and Surfaces: Milling PCB boards helps to add fine details and create a flat, smooth surface, which is essential for the overall functionality and aesthetics of the board.
Summary
Milling PCB board plays a vital role in electronics manufacturing. It's a high-precision, non-chemical process. Using a variety of equipment, including lasers, CNC routers, and carbide end mills, milling technology can precisely cut circuit board contours, creating complex shapes, fine details, and V-grooves. Whether used for rapid prototyping or mass production, it significantly improves the overall quality and functionality of PCBs, making it an indispensable component of modern electronics manufacturing.